Failure of effervescent zinc acetate lozenges to alter the course of upper respiratory tract infections in Australian adults

Abstract

Effervescent lozenges containing 10 mg of zinc acetate were evaluated as a treatment of upper respiratory tract infections in a double-blind randomized trial by using a placebo which was indistinguishable to most observers in taste and appearance from the active material. Of the 70 treatment courses used by 55 individuals in 34 families, 63 (33 zinc and 30 placebo) were considered evaluable, in that the volunteer used the medication at least four times daily for at least 3 days, the average utilization being 5.4 days at an average dose of six lozenges daily. Six users of zinc reported nausea (versus no placebo users), and eight reported an unpleasant taste or aftertaste (versus one placebo user). No benefit was observed among the users of zinc acetate. The mean duration of symptoms in users of the zinc was 12.1 days, compared with 7.7 days in those who used the placebo. Nor was any beneficial effect of zinc evident among the four zinc-treated versus the two placebo-treated individuals from whom rhinovirus was grown.

Zinc Gluconate and the Common Cold: A Controlled Clinical Study

“…In the literature quoting mean duration of a common cold, 3,[14][15][16][17] it has been specified that the cold is considered to have begun when one or more symptoms are present for 2 days, or two symptoms are present for 1 day. In the present study, the onset of the cold was defined a s t he ti me wh e n t he f ir st sy mpt om wa s recognized by the patient.…”

“…Attempts made to duplicate the success which Eby et al 1 had in 1984 in reducing the duration of the common cold using zinc gluconate have generally been disappointing, [2][3][4] the probable reason being that zinc gluconate was inactivated by additives used to mask its unpleasant taste. It has been demonstrated that of these agents, e.g.…”

“…It has been demonstrated that of these agents, e.g. citric acid, 2 tartaric acid, 3 or mannitol/sorbitol, 4 inactivate zinc by chelation in saliva. 5,6 Unflavoured zinc gluconate and the zinc gluconate -glycine (ZGG) lozenges used in the present study release 90 -93% of zinc ions, 6 whereas citric acid 2 and mannitol/sorbitol 4 formulations release no zinc ions when dissolved in the mouth.…”

Antipicornavirus Drugs: Current Status

“…However, no reduction in the rate or amount ofvirus shedding occurred. The results of further studies suggested that no beneficial effect resulted from the use of either zinc acetate or zinc gluconate Douglas et al, 1987;Geist et al, 1987). In addition, the results of a study involving the ingestion ofzinc where subjects ingested 300 mg day-l for 6 weeks indicated that there was a significant reduction in lymphocyte proliferative responses, polymorphonuclear phagocytic function and high-density lipoprotein concentrations (Chandra, 1984).…”

Failure of zinc gluconate in treatment of acute upper respiratory tract infections

“…Nasal mucous weights and number of tissues used were higher in subjects taking zinc gluconate. Douglas et al (2) used effervescent zinc acetate lozenges in subjects with naturally acquired URIs. There were no differences in effect on severity or duration of symptoms between zinc and placebo recipients.…”